added guidance note for rep checks

[luisesanmartin]

Guidance note is the same as in our internal DIME Analytics documents

[luisesanmartin]

Added a few changes on the week of Oct 21, 2022:

• Separated guidance note in a different file
• Changes to the guidance note text to improve the information it has, note that now it's different from the document we have on OneDrive:
  • Moved part of submission confirmation that was included in reproducibility check section, for clarity
  • Updated workflow diagram
  • Detailed checks evaluated in rep checks
  • Standardized technical terms: "pre-publication code review" is now "reproducibility checks", "paper outputs" now "paper exhibits"

[luisesanmartin]

Pending points from meeting on Oct 24 about rep checks:

• [x] add instructions for restricted-access data
• [x] add requirement to include folder with ado files in Stata packages

[luisesanmartin]

@mariaruth this is ready for review. Thanks!